<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <style>
        
    </style>
</head>
<body>
    
</body>
<script>

    class Parent{
        constructor(m){
            this.message = m;
        }
        show(){
            console.log(this.message)
        }
    }

    class Child extends Parent{
        constructor(m){
            super(m)
        }
    }

    const p = new Parent("hello world")
    console.log(p)
    p.show();

    const c = new Child("hello 世界")
    console.log(c)
    c.show();


    // 父类

    // 子类

    // 父类就是子类的超类



</script>
</html>